Automatic dental mallet



(No Model.)

\ H. M. FRY.

AUTOMATIG DENTAL MALLET.

No. 548,359. Patented Oct. 22, 1895.

INVENTOI? ANDREW .GGMMM. PHUTO'UVMO. WASHINEYU IlA IN.'`

Unirse dramas Partnr @ritiene HARRY MARKER FRY, OF JOHNSTOWN, PENNSYLVANIA.

AUTOMATIC DENTAL MALLET.

SPEOIFIGATIQN forming part of Letters Patent No. 548,359, dated October 22, 189 5.

Application ined December 20,1894. serrano. 532,510. CNO model-l .To all whom it' may concern:

Be it known that I, HARRY MARKER FRY, of Johnstown, in the county of Cambria and State of Pennsylvania, have invented a new and useful Automatic Dental Mallet, of which the following is a specification.

My invention relates to improvements in automatic dental mallets; and it consists of a single and simple instrument, as hereinafter described, held and operated by one hand. The particularobject sought to be attained by my invention is to provide a combination of levers with mallet or hammer attached whereby a direct blow of the hammer may be delivered sharply and quickly and at the same time either hard or easy, at the `will of the operator, upon the plugger-point held by the instrument. I attain this object by the mechanism illustrated in the accompanying drawings, in which-- Figure lis a full-size side view of entire mallet, with position of levers and hammer in the act of delivering a blow indicated by dotted lines. Fig. 2 is a full-size view of the front edge of entire mallet. Figs. 3 and 4 represent a longitudinal central section of mallet, showing the parts by which the plugger-point P and the shaft B are held, and also all other internal parts of mallet. Fig. 5 isa separate side view of the combination of iinger-piece, levers, connecting-link, hammer or mallet regulating-screw, and steel plate, with the two fulcrums attached, by means of which the particular object of my invention, as above mentioned, is attained.

Similar letters refer to similar parts throughout the several views.

A is the mallet-case, made of hard rubber and having a brass-tube lining in which the.

shaft Bis held to receive the plugger-point P at socket C in shaft B. The steel plate E, supporting the fulcrums H and J, in which, respectively, Work the levers G and I, is attached to the case A by the two screws D D.

F is the hammer or mallet attached to the outer and longer end of the curved lever Gr, which, swinging on the fulcrum H, raises or lowers the hammer F in the operations of the instrument.

K is the connecting-link communicating the motion of the lever l to the hammer-lever G.

N is the small adjusting-screw in the long lever I, which, by striking against the steel plate E, regulates the length of the stroke of hammer.

M is the ngenpiece on short or outer end of long lever I.

L is a steel spring to keep lever I in position.

O is a collar on shaft B, against which the small spiral spring Q rests to keep the shaft B up ready for action, so that when the hammer or mallet F strikes shaft B it plunges the plugger-point P into the filling. The other end of spiral spring Q rests in the end of detachable portion of mallet-case S, Fig. 3.

R is an oval kerf in mallet-case A permitting the thumb ofthe operator to turn the shaft B, and with it the plugger-point P, in any desired direction.

S is one end of mallet-case A with thread cut on the brass lining at U to screw'on the counterpart of brass lining at V.

The instrument is held between the thumb and rst two fingers of the operator, who by pressing with the end of the forefinger on the finger-piece M, attached to the shorter and outer end of long lever I, raises the opposite or longer end of that lever. This motion is communicated to the inner end ofthe hammerlever G by the con nesting-link K, which by being tilted brings down the hammer F at the other end upon the shaft B, holding the plugger-point P. By releasing the pressure of the finger on the finger-piece M the spring L restores the levers and hammer to position for another blow, as indicated in drawings. The operator is thus enabled by the power of his inger to regulate the force of the blow, striking fast or slow, or hard or easy, according to the character of the work. The force of the blow can also be regulated by the adjustingscrew N in the long lever I by giving to the hammer a long or short stroke.

l know that prior to my invention a hammer has been used in connection with a plugger-point. l therefore do not claim this broadly; but my invention is distinguished from all others by the special construction and combination of the levers G and l, their respective fulcrums H and J, the spring L, connecting-link K, and hammer F, whereby the resistance ofthe spring L is overcome by the power of the finger, and sharp, quick, and rapid direct hammer-blows of any desired de- IOO fulerum H and having on its Outer and longer curved end the hammer F, by means of which combination a direct blow of the hammer l may be delivered upon the end of be shaft r B holding the plugger pointP; all in manner as substantially described and for me pur pose hereinbefore specified.

HARRY MARKER FRY.

lvtnesses:

THOMAS J. ITELL, O. C. KOPELN. 

